package/mpd: bump to version 0.20.4

Signed-off-by: Jörg Krause <joerg.krause@embedded.rocks>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/mpd/mpd.hash

@@ -1,2 +1,2 @@
 # Locally calculated after checking pgp signature
-sha256  2238c1233f5318800ede7c37eeaf705c04920315de572dc666aff6ca682eb0f9  mpd-0.20.3.tar.xz
+sha256  712b25351c12616630c580204e1c3dcba3ae2993a56cff1c346c87e334d69728  mpd-0.20.4.tar.xz

package/mpd/mpd.mk

@@ -5,7 +5,7 @@
 ################################################################################
 
 MPD_VERSION_MAJOR = 0.20
-MPD_VERSION = $(MPD_VERSION_MAJOR).3
+MPD_VERSION = $(MPD_VERSION_MAJOR).4
 MPD_SOURCE = mpd-$(MPD_VERSION).tar.xz
 MPD_SITE = http://www.musicpd.org/download/mpd/$(MPD_VERSION_MAJOR)
 MPD_DEPENDENCIES = host-pkgconf boost